The present invention relates to the art of trucks and, more particularly, to improvements in dump trucks of the type including an integrated conveyor and spreader system for conveying material from a dump body to a spreader while facilitating the hauling of long items, conveying material through a tailgate opening, or the hauling/dumping of material without interference from auxiliary structures carried by the truck for use in conjunction with the integrated conveyor and spreader system.
Trucks, such as dump trucks, have been used heretofore to convey material such as salt, sand, dirt, gravel, and the like for the purposes of transporting the materials from one location to another and/or spreading such materials onto road surfaces to improve the road surface and/or traction of vehicles traveling thereon. Dump trucks have also been used to carry and dispense asphalt on road surfaces for repair and maintenance purposes and to transport elongated components such as steel rods, wood beams, and the like. Materials of a granular nature are commonly dispensed from the truck by tilting the dump body so that the materials flow therefrom by gravity and/or by conveying the materials within the dump body out through an opening in the floor of the dump body or through an opening in the tailgate thereof. Dump trucks with such integrated conveyor systems are shown, for example, in U.S. Pat. No. 4,886,214 to Musso, et al.; U.S. Pat. No. 5,397,172 to Musso, et al.; and U.S. Pat. No. 6,186,731 to Vickers, et al. In this respect, these patents disclose a dump truck in which the dump body or material receptacle is provided with an endless conveyor for conveying materials in the dump body to an adjustable feedgate mounted within an opening in the tailgate of the dump body for selective positioning relative to the conveyor to control the dispensing of materials from the dump body.
Other patents disclosing dump trucks and conveyor combinations are: U.S. Pat. No. 4,685,619 to Harder; U.S. Pat. No. 2,870,923 to Jewell; U.S. Pat. No. 5,170,947 to Houle; U.S. Pat. No. 4,583,693 to Harder; U.S. Pat. No. 5,400,974 to Musso; U.S. Pat. No. 5,466,112 to Feller; and U.S. Pat. No. 5,772,389 to Feller. The Houle patent discloses a particulate spreader with a dump truck that has a bed that can be tilted and a conveyor that has an end extending forwardly of the front wall of the dump body. The Jewell patent discloses a convertible dump body where the conveyor can be covered by plates which provide inclined side walls in the truck bed when the conveyor is uncovered. U.S. Pat. No. 5,772,389 to Feller and the patents to Harder disclose tilting truck beds and conveyors that dump material onto a spreader that spreads the contents. The Feller patent further discloses covering the conveyor when the latter is not in use. The other patents referred to are representative of further prior art regarding dump truck and conveyor combinations. The aforementioned patents are incorporated herein by reference to provide background information with respect to the type of vehicles and conveyor arrangements to which the improvements according to the present invention are applicable.
The prior art devices in the above patents are conveyors and/or spreaders which are permanently and/or fixedly attached to the truck chassis and remain attached even when the dump truck is used for dumping materials. The conveyor and spreader apparatus is not protected from exposure to adverse weather when not being used for spreading, and is not protected from other damage attendant to having the conveyor and spreader arrangement permanently attached to the vehicle. Additionally, if the dump truck is used for dumping gravel or stone materials, the position of the conveyor and/or spreader apparatus relative to the tailgate does not preclude abrasive contact of the material being dumped with the component parts of the conveyor/spreader apparatus. All of these problems result in increased maintenance time and cost in connection with repairing damage to component parts or replacing the parts. Consequently, there remains a need for a conveyor and spreader assembly to be used with a dump truck which overcomes the aforementioned problems and limitations.
In accordance with the present invention, a conveyor and spreader assembly is provided by which the foregoing and other disadvantages and problems with conveyor and spreader assemblies heretofore available are minimized or overcome. More particularly in accordance with one aspect of the invention, a conveyor and spreader assembly is removably mounted on a dump body whereby, during periods of non-use of the conveyor and spreader assembly, the latter can be easily removed so as to provide for use of the dump truck for other purposes without interference from or potential damage to the conveyor and spreader components. More particularly in this respect, the dump truck can be used for hauling a variety of materials which can be dumped when the tailgate is released for pivotal movement to an open position and, with the conveyor and spreader removed, such dumping is achieved without any potential interference from or damage to the component parts of the conveyor and spreader. Moreover, the tailgate can be pivoted relative to the truck bed about a horizontal axis adjacent the lower end of the tailgate, by which the latter can be opened to a flat condition coplanar with the bottom of the truck body. In this manner, the tailgate provides an extension for the hauling of elongated objects such as trees, lumber, pipes, and the like.
In accordance with another aspect of the invention, the conveyor and spreader components can be extended and retracted relative to the rear end of the truck, whereby the dump truck can be temporarily configured to be used as a typical dump truck as described above when the conveyor and spreader assembly is retracted. When the conveyor and spreader is extended outwardly of the rear end of the dump body, material in the dump body can be moved rearward by the conveyor and onto the spreader for discharge rearwardly of the dump truck.
The ability to remove the conveyor and spreader assembly from a truck and to extend and retract the assembly relative to the truck when it is mounted thereon advantageously promotes versatility with respect to use of the truck and versatility of the use of the conveyor and spreader assembly when the latter is on the truck. Mounting and removal of the conveyor and spreader assembly from the dump truck is simple and easy to achieve so as to minimize the time and effort required to mount and remove the assembly. It will be appreciated that when the conveyor and spreader components are not in use and are removed from the dump truck and suitably stored, they are protected from exposure to adverse weather and/or other potential damage attendant to having conveyor and spreader components permanently attached to the vehicle.
It is accordingly an outstanding object of the present invention to provide improvements in connection with conveyor and integrated spreader mechanisms in dump trucks selectively used for hauling and discharging materials from the rear end of the dump body, either by elevating the dump bed or through the use of a conveyor/spreader mechanism.
A further object is the provision of a conveyor and spreader mechanism which allows the dump body of a truck to function in an improved manner as a typical dump truck or in conjunction with the conveying and spreading of particulate material.
Yet another object is the provision of a conveyor and spreader mechanism which can be readily mounted and removed from a dump body of a dump truck and which, when mounted, can be extended and retracted relative to the rear end of the truck.
Still a further object is the provision of an improved conveyor and spreader mechanism which, in combination with a dump body, optimizes the material hauling capabilities of the dump body.
Yet a further object is the provision of an improved conveyor and spreader mechanism which avoids the maintenance and/or replacement costs heretofore encountered as a result of the conveyor and/or spreader being permanently mounted on a dump truck and thus being on the truck during periods of non-use of the conveyor and/or spreader mechanism.
Still another object is the provision of an improved conveyor and spreader mechanism which optimizes protection of the conveyor and spreader components from damage and/or interference with materials being hauled and/or dumped by the truck during periods of non-use of the conveyor and spreader mechanism.